The Long Term Evolution (LTE) standardized in the 3rd Generation Partnership Project (3GPP) uses system information formed of multiple SIB (System Information Blocks).
Among the multiple SIB, a SIB1 is defined such that the SIB1 is transmitted by using Subframes #5 in Radio frames with even-numbered System Frame Numbers (SFN). A transmission periodicity of the SIB1 is 80 msec; specifically, the SIB1 is transmitted at 20 msec intervals four times (one first transmission and three retransmissions). Meanwhile, SIB (SIB2 and following SIB) other than the SIB1 are mapped to SI-windows of a downlink shared channel and transmitted in units of SI.
FIG. 11 shows mapping and a transmission image of the SIB other than the SIB1. As shown in FIG. 11, the size of the SI-window is common to the pieces of SI (SI-1 to SI-3) (notified in the SIB1). The SI-windows are defined such that each SI-window does not overlap any other SI-window in a time axis direction. Moreover, regarding each piece of the system information (SI), the SI (for example, SI-1) is transmitted in the SI-window of 20 msec set in each predetermined periodicity (SI-periodicity).